Telephone system



W. M. BEAUMONT TELEPHONE SYSTEM FiledAugust 20, 1925 I I` i u i q Patented Dec. 2l, 1926.

TED, STATES XVILLAM Ii. BEAUMONT, OF SUMMIT. NEW JERSEY, ASSIGNOR TO BELL TELEPHONE LABORATGRIES, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE SYSTEM.

Application filed August 20, i925. Serial No. 51,299. i

This invention relaties to telephone systems, and more particularly to improvements in operators connecting circuits equipped 'for establishing connections to subscribers lines that may be reached by manually extended connections or by automatically operated means under control o'l' the connecting circuit employed.

ln systems ot this type it is common practice to employ in the case of a manually extended connection to the subscribers line a common master ringing key circuit that is automatically associated with the connecting or cord circuit taken for use. This common key circuit may be manipulated to transmit diiterent types of ringing current in ditleilent manners over the connected subscribers line to call corresponding parties thereon. lt is also common practice to employ cord circuits of this type whereby it the desired subscribers line can only be reached through automatically operated switching devices, a dialing equipment common to a plurality oi cord circuits is automatically connected to the cord circuit employed and whereby the manipulation oi' this dialing equipment controls the selection through said switching devices ci the desired subscriber. The arrangement is usually such that after the dialing and common master ringing key equipments are automatically associated with a cord circuit the release therein will take place upon the actuation of a manually operated key when the dialing equipment alone has been employed in auton'iatie` connections and that the release of said equipment will take place automatically after the master ringing equipment has been employed in a manually extended connection.

lt is an object oi this invention to improve cord circuits ot this general character to perform the functions for which they are designed in a more expedient and eiiicient manner than heretofore.

To attain this and other objects oft the invention, as will hereinafter appear, there is provided means whereby the usual impulse fender, in the common dialing equipment when associated with a cord circuit taken ior use, is automatically connected to this cord circuit only on the operation ot the sender from its normal position.

Another feature of the invention resides in means whereby after the sender has once been connected to a cord circuit, it cannot be released therefrom until a manually operated key is depressed and the sender itself has returned to normal position.

The invention has been illustrated in the accompanying drawings, in which Fig. 1 shows a systemwhereby a connection may be extended from an ordinary subscribers line 1, over arcord circuit 2, arranged in accordance with this invention, and from this cord circuit to an ordinary subscribers line 3, while Fig. 2 shows the outgoing end lof a trunk line 4, whereby a connection may be extended from cord circuit `2 to a distant automatic exchange where a desired subscribers line may be reached through the operation of automatically actuated switches. Referring now to the drawings, the cord circuit 2 represents one of a plurality of similar cord circuits at an opeiators position, with which the common equipment 5 shown below the dash-dotted line may be associated in succession, as required for the successful manipulation ofv connections established. by said cord circuits. VThis common equipment comprises a dialing circuit G, including an impulse sender 7, and a master ringing key circuit 8, including party line ringing keys 9, 10, l1 and l2, whereby any one of four parties on a connected subscribers line, such as 3, may be rung, and a .so-called trunking key 13, whereby the dial ing. equipment 6 and master key ringing equipment 8 may be disconnected from a cord circuit when it is of no further use in the establishing of a connection.

To more clearly bring out the variousfeatures ot the invention, a description will iirst be made of thev functions of the system illustrated in the establishing of a connection between line 1 and line 3, through cord circuit 2, followed by a descriptionot a connection between line l and a trunk 4, through the cord circuit 2, and parts played by the common dialing and ringing equipments in connections of these types.

Assuming then that the operator at the switchboard where cord circuit 2 is located observes in the usual manner that a connection is `desired by the subscriber connected to line l, she will insert plug l5 of the cord circuit 2 in the multiple jack i6 of line l.

lOl)

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Battery is connected to lead 2O through the action of any well-known sequence circuit so that the operators telephone circuit will be connected in succession to engaged cord circuits. In this case therefore this bat tery will be supplied lover lead 2O through the lower outer armatureand back contact of relay 21, outer right-hand armature and bach contact of relay 22, winding' of relay 22, sleeve terminals of plug and jack 16 through a resistance to ground. This cir-- cuit causes the operation ofrelay 22, which in operating alsocloses a circuit through its 1nalte-before-lneali contacts to battery at the u1al-:e-before-break contacts of relay 21 and opens its original energizing circuit to battery on lead 2O This relay will, therefore, be locked under control of relay 21. The operation of relay 22l also closes a circuit for the operation of relay 25, as follows: batter-y, inner right-hand arma-ture` and another front contact .of .relay 22, winding of relay 25, 1nake-beforebreak contacts of lrelay 26 to ground. Relay 25 operates in this circuit and associates the common. equipments 5 with cord. circuit 2 by ,closing at its Various armatures andfront 4contacts anumber of circuits the purpose of which will appear as the` description proceeds. One of the circuits closed bythe operation of relay will be a circuit .from the operators telephone set connected atOT, to the 4tip and ring conductors of cord circuit 2. This circuit may be traced as follows: from the tip conductor-of cord circuit 2, inner right-hand armature and front contact of relay 25, upper armature and back contacto-f relay 27, the tip conductor through the operators telephone set, back through the ring conductor of the set, upper outer armature and baclt'contact of relay 28, normally closed offnorinal contacts 30 of dial 7, inner left-hand armature and front contact ofrelay 25 to the ring conductor of cord circuit 2. The operator is now, therefore, connected tothe calling subscriberseline through the repeatf ing coil 23 and may ascertain the number of the wanted subscribefs line. Tf, for example, a subscriber' on line 3 is desired, this subscriber may be rung -by the operation of a corresponding keyin the common master ringing key equipment 8. A

The first action on the part of the operator towards accomplishing this purpose will of course be to insert plug 31 in jack 32 of line 3. A circuit is thereby closed for the operation of relay 21, as follows: battery, winding of relay 21, sleeve terminals of plug 31 and jack 32, through a resistance to ground. The operation of relay 21 results in closing its inner lower armature to the corresponding front contact to extend the locking circuit for relay 22 to a battery connected at the arniature and front contact of relay 2%, so that relay 22 is now locked under control of this latter relay. Another circuit closed by the operation of relay 21 is a circuit for supervisory lamp 33. This circuit may be traced as follows: battery, upper arinature and front contact of relay 21, lamp 33, arniature and back contact ot supervisory relay 3l to ground, so that lamp 33 now lights to indicate to the operator that cord engaged. The operation of relay .21 also closes an additional circuit tor the operation of relay 35, as follows: battery, lower iniddle armature and front Contact of relay 21, upper inner armature andv back contact of relay 26, winding of relay 35 to ground. The operation of relay 35 closes an obvious circuit for the master ringing and dialing equipment lamp 36 to indicate to the operator that these equipments are engaged in a connection.

Willen the operator finds lamp 35 lighted she dcprcsses the ringing key of the desired party on line 3. lf the party desired is party M, she operates key 9. This closes an obvious energizing circuit for relay at() and relay 4l() iny energizing closes a locking circuit for itself through its lower armature and front contact to ground at the upper armature and frontcontact of relay The operation of relay l0 also closes an obvious circuit for the energization of relay Rclay 42 in operating closes a circuit for the operation of relay 43 as follows: battery, lower armature and front contact of relay ft2, lower inner armature and front contact of relay 35, middle left-hand armature and front contact of relay 25, winding of relay 43, armature and back contact of ringing trip relay 44: to ground. The operation of this relay closes Various circuits as will here inafter appear. The operation of relay 412 closes an obvious circuit for relay f5 which in energizing closes a circuit for the operation of relay 2G as follows: battery. upper aru'iature and front Contact of relay 2l, windingl 'of relay 2G, outer right-hand armature and front contact of relay 25, armature and front contact `of relay L15 to ground. Relay 26, in operating, closes a locking circuit for itself iiulepcndcnt of thc ground at the armature and front contact of relay .45 through its own lower arniature and front contact tc ground.` The operation of relay 2G inopeir ing its own 1nalte-before-breah contacts to y 44, lower outer armature and ground opens the circuit for relay25 which now deenergizes and disconnects the n'iaster loe noted, however, that hetore rela, 25 is deenerfrized a circuit is closed thi-ouch the .oir

b i .en l

eration of relay 40 tor the operation ot re-V lays 4o and 4?'. ot relay 46 is inatuie and front contact ot relay 2l, winding; oi relay 45, out-er lett-hand arinature and front contact ot relay lower outer arinature and hack Contact ot reli 2T, upper armature and liaol; Contact of reli y 28, upper arinature and iroiit contact ot'v relay 40Y to ground; 'llie circuit `iior relay ai inay he traced as follows: battery, armature and l'ront contact of relay 2l, winding` ol relay 4T, iniddle right-hand armature and 'lroni Contact ot' relay 25, upper armature and another :trent coi'itact ol relay 40 to ground. The operation of relay connects ground at its lower inner armature and iront contacts through the lower outer arinature and t'ront Contact ot' relay 43 to the ring terrninal 'he circuit tor the operation 'of plug 3l and the operations of relays 4G and 47 connect positive potential ringing` current 'from the ringing 48 through the upper windingl ot tr ping relay :ont Contact of relay 47, upper outer arinature and l'ront Contact of relay 46, upper outer armature and Yfront contact ot relay 43 to the tip terniinal ott plug 3l. .lt should he noted that relays 43, 46 and 4T when operating provide locking circuits for themselves to thegreuud at the armature and back contact of tripping` relay 44. The locking; circuit tor `iela-y'43 being' closed through its upper inner arinature and front contact, thelocking circuits for relay 46 being closed through its upper inner armature and frontcontact, the locking; circuits for relay 46 being; closed through of relay 25 so that whenrelay 25 deenei-v The. ringing' current trein source 4S and hach to Aizizes, these relays are not al'lected.

ground is applied through the tip and ring;r terminals ot plug' 3l and transn'iitted in th`x usual manner to ring' the fauted suhscribers bell. that is, with the @ground on the ring conductor and with the positive ringing' current ou the tip conductor the hell ot party hl on line El is rung'.

lit the party J had been the party wanted.

lev l0 would have heen operated and relay 49 would have heroine energized. Yl`he lunc- `tions ol the inaster ringing; hey equipment as follows: battery, upper ar-v Vexcept that relay 46 will not operate.

and the cordv circuit would inthis case have heen ident-ical with the functions previously' described when party M was called, except trat relay 4T is not energized. lt should he noted thi.

front vcontacts or" relay 49. "therefore, iiistead of current troni the positive ringingl` source 48 losing` transmitted over the tip conductor of the cord circuit 2 to line 3, negative ringing current is transmitted over this conductor trein source 50 as follows: source 50, lower winding of the ringing` trip relay 44, upper outer armature and iront Contact oit relay 26, `lower outer armature and back contact of relay 4?, upper outer armature andrtront contact of relay 46, upper `outer armature and Jr'roiit contact ol'. relay 43 to the tip terminal ot plug 3l and jack 32 over the tip conductor ojt line 3, and intrus in; stance the hell oit party J will he operated.

lt the party desired had heen party ll, key

l wouldhave been operated to close an ohvious energizingl circuit for lrelay 5l.v lnl this instance the operations will 'he the saine ln this instance then the positive ringing current i'froin source 48 and ground will he connected in reverse manner to the tip and ring terminals of plugl and it' party lV had been the party desired, relay 52 would have been operated and in this instance, the current troni the negative ringing current source 50 and ground would have heen connected to the tip and ring` conductors in reverse manner, as in this instance neither reated.

ot a wanted subscriber current is induced troni the tip and ring leads ot the cord circuit 2,,through the repeating coil 23 by the presence of the condensers .33 and 54y in the tip and ring conductors ot cord circuit 2. The calling suhscriher will, therefore, hear the ringing ot the wanted subscriber as is well known in the art. *Y 1 lhen the called. subscriber answers by romoving` his receiver troni they lioolr, the ringing trip relay 44 will operate as is well known in the art and release the relays 4t?, 47 and 43 and disconnect the ringing source t'roin 'the conductors otl they cord circuit. The release of relay 4?) short circ iits the condensers and 54 so that the circuit will. now he completed through the subscribers loops troni the battery and ground at the righthand windings` ot repeating coil 23 and supervisory relay 34 is new operated in this circuit. The operation ot this relay extinguislies the lainp 33 to indicate .to the oper- V no ,energizing` circuit` will be` 'closed for this relay at the armatures and It should he noted that during the ringing V scriber hangs up his receiver on the hook, supervisory relay 24 is released, causing the release ot relay 22. The release ot relay 22 closes a circuit for the lighting of lamp 55. This circuit may be traced as follows: battery, upper armature andV front contacts of relay 2l, lamp 55, lett-hand armature and back contact of relay 22 tog-round. The lighting ot this lainp indicates to theoperator that the calling` subscriber` has released and she may now remove plug' l5 'from jack 1G and plug 3l from jack On the rcmoyal otl plug 3l, relay 2l released and lainp extinguished.

A connec'ion extended through the trunk 4 to a subscriber that may be reached by the operation ot automatic switcheswill now be described. The 'function ot' cord circuit 2 in connecting the common master ringing vkey and dialing equipments 5 to trie cord circuit is the same as previously described up to the preparation oif the cord circuit for the insertion ot plug 3l in tliejack of the line to which the connection is to rbccX- tended.

If now the operator inserts plug 3l in jack t3() of trunlr4 the following circuit is completed: battery, winding ot relay 2l, sleevey terminals Vof plug 3l andjack 60, winding of relay Gl to ground. This circuit causes the operation of relays V2l and 6l. The operation ot relay 6l causes an obvious energiz ing circuit to be closedltor relay 62, and relay 62 when energizingcloses a 'circuit 'for relay 63. as follows: battery,lowerrighthand winding ot repeating coil23,/winding of supervisory relay 34, lower outer-armature and baci; contact of relay 48, ring terminals oi' plug 3l andjack 60, malte-beforeloreak contacts of relay 63, Winding of relay (33, armature. and iiront contact otrelay 62 to ground. This causes the operation otrelay 68 which now provides aV locking circuit ior itself independent ot the'battery at'the repeating coil 23. This locking circuit is completed through the lower outer armature and front contact of 'relay 63 to battery. The operation ot relay 63 also closes the tip and ring conductors ot' trunl`4 through't'rom the line side to the outward end of the trunk. The operation ot relay G3 also' cl'oses an obrious circuit for relay 64 and the operation ot relay (i4 closes a circuit across'the'tip and ring conductors ot the trunk through the retardation coil 65 and relay 67. Relay 67, however', does not operate at this time as this relay is polarized and does not respond to the current incoming over the trunk 4 as it is of a direction opposite to that to which 'relay ($7 would respond. The lighting of lamp 3G as previously described indicates to the oper` ator that the ringing 'key and dialing equipments are lconnected to the cord 2 and that the dial 7 may be manipulated to select the wanted subscrihefs nui'nloer.

neuf/11 T now the operatorv manipulates dial 7 in accordance withv the wanted subscriber-s number the contacts 3() are opened as the dial moves voit-normal and contacts GS are closed. At the closing of these contacts a circuit is closed for the operation orn relay 27, yinthe dialing circuit, and relay 69, in the outward end of the trunk circuit 4, as follows: battery, lower outer armature and front contact ot relay 63, winding relay G9, armature and back contact of relay G7,

ring terminals ot' jack 60 and plug 3l, lower outer armature and baclr Contact of relay 43, inner left-hand armature and trontcontact of relay 25, olii-normal contacts G8 ot dial 7, winding'ot relay 27 to ground. The operation of relay 69 closes an obvious energizing circuit for relay 70, The operation ot this'relay closes at its upper inner armature and front Contact the tip side of the cord 2 from the ground at the upper right-hand winding ot repeating coil 23 through to the winding ot' relay (i4 so as to maintain relay G4 operated until the circuit irom the pulsing contacts 74 ot dial 7 is completed as will hereinafter be described. This relay also opens vat its inner lower armature and back contact a connection to ground through a resistance and one side of the winding of relay 7l. Relay 70 also closes at its outer lower armature and front contact a shunt circuit across the line side ot the trunk 4. This shunt circuit is now under control of the'arinature and front contact'ot relay 64 s0 that at each operation and release `of relay 64, as will be hereinafter described,'the line side'ot the trunk will be alternately opened and closed. lt should be'noted that the operation of relay 70 also disconnects the line side'of trunlr4 from the outgoing end at its outer upper and lower armatures and back contacts. On the operation ot relay 27 the tip conductor from t-he. cord 2 to the: operators telephone at 0T is disconnected at the upper armature and bacli contact of this relay. Relay 27 also closes a circuit for relay 46 as follows: battery,

upper armature andrfront Contact ot relay 21, winding of relay `46, outerl le'ftdrand armature4 and front' contact ot' relay 25, lower outer `armature and vjtront contact of relay 27 to ground. Relay 46 in operating disconnects theground connection trom the upper right-hand winding ot repeating coil 23 to the tip conductor ot' the cord. but as this conductor is now connected through the inlner right-hand armature and front contact closing ol. contacts 68 oi dial 7 between digits. This circuit may be 'traced as follows: V'roin the battery, at the lowerarmature and liront contact ot relay 63, through the ring conductors ot trunk 4 and cord 2 as lxei'enlieioi'e described to the innerletthand armature and liront contact of relay and from there. through the lower armature and liront contact oi. relay 75, lower outer armature and bacl: contact ot relay 76, windingl of relay 27 to ground. Relay 75 also closes an obvious energizing circuit :lor relay 28 which at its upper armature and back contact opens a circuit controlled by relays andr 49 to prevent the inadvertent operation ot the keys 9 and 10` from ctecting the setting of the relays in cord circuit 2 at this time. Relay 28 also opens at its upper outer armature and back contact the ring conductor tothe operators telephone set at 0T. e

YlVhen now the impulse sender or dial 7 is released to send the first series of impulses, contacts 74 are alternately opened and closed a number oi times in accordance with the number of the iirst digit. Relay 64 is thereby alternately operated and released to alternately close and open the line side ot the trunk 4. As is well-known inthe art, this opening and closing oit the tip and ring conductors of trunk 4 will cause switching operations to take place at the distant end in the automatic ol'lice tor the selection oi the wanted snbseribes line. yllhe subsequent operations of dial 7 in accordance with the remaining digits will have similar switching eiiiects at the automatic office, so that when the last digit is dialed the subscribers line will be connected to trunk 4.

The operator will now in Vorder to connect 'the calling and called subscriber together through the cord 2 and disconnect the common equipments 5 operate key 13. The operation oit this key closes an obvious energizing circuit for relay 76 which in ener-- gzing locks to ground at the armature and front contact of relay The operation of relay 76 opens the holding circuit for relay 27, which in releasing opens the circuit for relay 7 5. Relay 7 5 in releasing opens the energizing circuit tor relay 28, but as both these relays and 28 are slow to release, a crcuit is temporarily closed on the release ol relay 27 from battery, through the upper inner armature and front contact of relay 28, lower outer armature and back Contact ot relay 27, outermost lefthand armature and contact of relay 25, winding of relay 46 to cause the release ot relay 46 which it should be noted is locked to the ground at the upper armature and back contact of ringing trip relay 44 through resistance 14. rllhe release of relay 46 closes the connection from ground at the upper right-hand winding of repeating coil 23, through to the tip tcrn'iinal ot plug 31, so as to niaintzfiin relay 64 operated after relay 27 is released. .lt should be noted that between the release et relay 27 and betere the release ot relays 28 and 46 a ground connection for the maintenance of relay 64 operated over the tol# relay 70 connects relay 64 to ground at theV lower Contact ot relay 63, thus holding it operated, opens the short circuit about relay 67 and closes the tip and ring conductors of the trunk. A circuit is now established by the release o1' relay 28 for the op eration of relay 26 as follows: battery, upper armature and a front Contact ot relay 21, winding ot relay 26, outer right-hand armature and `iront contact ot relay 25, upi per armature and tron-t contact ot relay 76,

lower outer armature and baci: contact oi relay 28 to ground. The operation oi relay 26 now causes the disconnection ot the coniinon equipments 5 in the same manner as hereinbefore described. Relay 76 in the ringing key equipment8 releasedon the release of relay 35 in this circuit As is also well-lnown in the art when the subscribers line is reached, it is automatically rung Yfrom the automatic oitice and when the called subscriber answers, the battery connected to the trunk 4 at the auto matic office will be reversed, causing the operation of relay 67. The operation of relay 67 disconnects relay 69 from the ring conductor. Relay 67 in operating, closes a cir cuit from battery through the right-hand lower winding of repeating coil 23, winding of relay 34, lower outer armature and back contact of relay 43, ring` terminals of plug 31 and jack 60; armature and `liront contact of relay 67, winding of relay 71 through the tip conductors ot the trunk and cord circuit to ground at the repeat-ing coil 2. This circuit causes the operation of relay 34 which now opens the circuit ttor lamp 33 so that this lamp is extinguished and theres by notifies the operator that the wanted subscribers line has been found and connected to trunk 4.

The connection is now complete between the calling and called subscriber with relays 22, 21, 24 and 34 in the cord 2 held operated and with relays 71, 61, 62, 63, 64 and 67 in the trunk circuit held operated.

It thc key 13 is operated bc l'oie the scud-V ingof the last digit is completed, relay 27 will not release. iis the off-normal contacts ($8 ot dial 7 are still` closed and thus maintain the circuit for this relay closed until the dial has returned to` normal, at which time, the release oi the circuits take place as liereinbetore described.

In accordance with this invention, therefore, the dial. is not `connected to the cord circuit 2- until it has been moved ott-normal and its ofi-normal contacts 68 have been closed and neither can the dialing' circuit equipment 6 be removed from cord 2 until the dial has returned to normal and key 13 has been operated.

`What is claimed is:

l. In a telephone system, lines, cord circuits, a ringing key and dialing equipment common to said cord circuits, means for associating said equipment with acci'd circuit responsive to the connection of said cord circuit to a line, means `for disassociating said equipment from said cord circuit jointly i'esponsive'to the extension of said cord circuit to another line and to the oper ation of the ringing key in said equipment.

Q. In a telephone system, lines, cord circuits, a ringing key equipment and a dialing equipment both common to said `cord circuits, means for associating said equipments With a cord circuit responsive to the connection of sai-d cord circuit to a line, means for disassociating` said equipments i from said cord circuit jointly responsive to the extension of said cordcircuit to another line, to the actuation and release of the dialingl equipment and to the actuation o t a key in` said ringing key equipment.

3. in a telephone system, lincs, cord circuits, a` dialing circuit includingv a sender operated key and a circuit arrangement 't'oi'V disconnecting the sender and disassociating,I

the dialing circuit from said cord respon-,

sive, to the joint control over said circuit a rrangeinent by the actuation of the key and thereturnoi' the sender to normal position.

4. 1n a teiephone system, a line, a cord circuit, an impulse sender, means for connecting the impulse contacts of said sender to one conductor ci the cord circuit responsive to the connection of the cord circuit to said line and the operation of the sender, said connection being controlled over a circuit inciuding another conductor of said cord circuit and the ott-normal contacts or' said sender, and means for disconnecting said sender from the cord circuit responsive only on the openingf ot the control circuit by the off-normal contacts ot the sender on the return ot said sender to normal position.

In witness whereof, I hereunto subscribe my name this 17th day of August A. D., 1925.

VILLIAM M. BEAUMONT. 

